The global efforts on preserving the health of the planet are focused in some key area like global warming and environmental air quality. One aspect of improving environmental air quality relates to technologies where the carbon dioxide that is released from manufacturing processes is captured and sequestered.
Capturing and sequestering carbon dioxide may in the near future involve tightly controlled processes that include continuous real-time monitoring of carbon dioxide emissions. The processes and monitoring that are typically associated with capturing and sequestering carbon dioxide often require high cost-high power carbon dioxide sensors.
One potential technology that may be utilized to produce low-cost and low-power carbon dioxide sensors involves integrated resonant sensing technology. This integrated sensing technology is based on vibrating beams that are functionalized for chemisorptive carbon dioxide capture. The beams are typically doubly clamp (nano)beams, cantilever (nano)beams or even nanowires. The beams change their resonance frequency proportional to the amount of CO2 adsorbed on the beam.
These functionalized resonant sensing beams are typically located on the same chip with an integrated circuit for processing signals from the carbon dioxide sensor. A typical single silicon wafer having diameter of 400 mm may contain hundreds of thousands of on-chip carbon dioxide Nano-Electro-Mechano Sensors and Integrated Circuits (NEMSIC) that communicate with the readout integrated circuit.
One of the drawbacks with existing resonant NEMSIC gas sensing systems may relate to the baseline drift of the chemical sensor. The baseline drift is typically caused by the harmful effects of temperature variation, humidity and aging of the functionalized beams. These harmful effects often reduce the accuracy of the sensor response.